Problem: $ -\dfrac{2}{5} + \dfrac{20}{25} - 1.6 = {?} $
Solution: First get all of the numbers in decimal form. $ -\dfrac{2}{5} = -0.4$ $ \dfrac{20}{25} = 0.8$ Now we have: $ -0.4 + 0.8 - 1.6 = {?} $ $ -0.4 + 0.8 - 1.6 = -1.2 $